This invention relates to a powered detergent dissolution apparatus of a washing machine.
In general, the washing process of a washing machine has to employ a detergent to effectively wash clothes etc. some detergents are in powder form. Even after rinsing the powder detergent out of the clothes several times (about 4 times), some constituent of the detergent remains in the clothes. To avoid this, the detergent should be dissolved in advance with water outside of the washing machine and the dissolved detergent be poured into the tub of a washing machine. This calls for a mechanical detergent dissolving apparatus which prevents the power detergent from remaining on clothes.
Meanwhile, for the detergent to be dissolved, the attractive force between the solute (detergent) molecules must be less than the attractive force between the solute molecule and solvent (water) molecules. That is, the detergent is dissolved when the force attracting the detergent molecules to the water molecules is greater than the force drawing the detergent molecules together. When the adherence of the solute particles, i.e. a lump of detergent, becomes separated into solute particles, a contact area between the solute molecules and the solvent molecules is increased so as to achieve rapid dissolution.
The steps in a course of dissolution comprise a first step in which water permeates into a body of detergent and every particle is separated, a second step in which detergent particles are mixed with water so as to be broken into molecules, and a third step in which detergent molecules are dissolved with an ionization. The factors accelerating the separation and the dissolution of the particles are for example, the nature of the components of the detergent, or temperature of water, etc. The critical factor is physical flow energy applied externally. The stream force of the water stream applied against the detergent is doubled to increase energy. The best way to double the stream force is the nozzle force increase method utilizing a faster stream speed or a reduction in the crosssection of the nozzle.
A conventional detergent dissolution apparatus of a washing machine, using the force of the stream jetted from a nozzle, is shown in FIG. 5. A water supplying valve 110 having a nozzle 111 and an air intaking opening 112 is connected to the body 120 of the apparatus. In the interior of the body, there is provided an interior case 130. A filter 140 which is formed as a funnel or a truncated cone is placed in the interior case 130. The stream speed is increased as the crosssection of the outlet of the nozzle 111 is reduced, while further the speed is also increased as air is intaken through the air passage 112. This is due to the pressure decrease of the circumference of the nozzle outlet 112. The faster stream strikes against the detergent contained in the filter, and the stream passing through the filter vortex, as shown by arrow "D", in the interior case 130 for despersion of the detergent. The apparatus further provides an auxiliary filter 150 spaced from the outlet of the nozzle 111, thereby preventing the detergent from flowing back into the valve 110.
It can occur that a mass a of detergent particles is separated by the force of the stream and becomes disposed at the upper edge of the filter 40. The detergent particles are to be dissolved during the circulation of the particles in the interior case. When the stream pressure is in the lower (weaker) state (about 0.8 kgf/cm.sup.2), the force acting against the mass A is too weak to dislodge the mass. Thus, and the mass of detergent still remains at the upper edge of the filter. That force can be analyzed as follows.
From the impulse and the momentum equation, the fluid force F of the outlet of the nozzle is generally given by EQU F=e x Q x v (1)
where
e=density of fluid, kgf/cm.sup.3 PA1 Q=volume of fluid, 1/min PA1 V=speed, m/s PA1 H.sub.1' =resistance of auxiliary filter, kgf PA1 H.sub.2' =resistance of detergent height, kgf PA1 H.sub.5' =resistance of detergent filter, kgf PA1 L'=weaken force according to loss of fluid volume, kgf PA1 .beta.=reflect degree of fluid stream, deg.
Since the speed V of the fluid having a predetermined volume Q is decreased after leaving the nozzle, the force F'.sub.2 acting against the mass A given by EQU F'.sub.2 ={eQV-(H.sub.1' +H.sub.2' +H.sub.5' +L')}tan .beta.(2)
where
Wherein, H.sub.2' can be disregarded because it diminishes quickly during the dissolution of the detergent. Comparing this equation with equation (1), the initial force is weakened as a function of the resistance of the auxiliary filter H.sub.1', the resistance of bottom of filter H.sub.5', the loss of fluid volume L', and the value eQV tan .beta..
Moreover, the detergent particles which overflow from the upper periphery of the filter, with the water stream "B", will in the initial stage of the water supply, accumulate in the lower corner portion C. Consequently, the streamline water current D can not contact that accumulated detergent so it remains, which causes other problems. For example, remaining detergent continues to dissolve until the last stage of the water supply cycle, and makes bubbles during the rinsing cycle. The bubbles flow into the tub or flow up from the gap between the body and the opening.
Furthermore, since the detergent particles are undissolved at the initial stage or the main water supply stage when the stream has high pressure, those particles fully occupy the filter, reduce the outgoing water volume to a value less than that of the incoming water through the nozzle. Also, a lump of detergent particles entrained in the water is are reverse-flowed out from the top of the detergent container (F). To solve the problem, the gap G, through which the detergent flows out, needs to be narrower. The more the gap is narrowed, the more the detergent dissolved in the water flows backward through the air inlet 112 of the water supply valve (in the absence of filter 150). This phenomenon continues for an extended period, because the reduced-pressure water stream cannot quickly dissolve the detergent. The problem becomes more serious as the substance (soup) in the filter becomes more sticky. To solve this problem, the filter 150 is installed at the outlet of the water supply valve, but this too becomes a factor in reducing the nozzle jetting force.